Spread spectrum system performs data transmission by using a frequency band with its bandwidth much greater than information bandwidth, has advantages of anti narrow band interference, anti multi-path fading, good security, high spectrum efficiency and being applicable to cellular networks, and becomes a widely used class of wireless communication technology. For example, in wideband code division multiple access (Wideband Code Division Multiple Access, referred to as WCDMA) system, a receiving end device can adopt a transform domain suppression mode to suppress narrowband interference (Narrow Band Interference, referred to as NBI) signal.
In prior art, according to bandwidth and strength of a NBI signal, a receiving end device can obtain the number, 2M, of the frequency points which are to be set to zero in frequency domain signals obtained by transforming sample data, then the frequency domain signals at left M frequency points and right M frequency points around a detected interference central point are set to zero, and then despreading is performed to a time domain signal obtained from transform.
However, the transform domain suppression mode in prior art sets the frequency domain signals at the 2M frequency points to zero, which not only filter out the NBI signal, but also filter out the useful spread spectrum (Spread Spectrum, referred to as SS) signal, thereby reduces the reliability of signal reception.